In the case of a radiation-emitting body containing an optically dense material, radiation generated by the body can be subjected to total reflection at the transition to an optically dense medium and be reflected back into the body. The radiation is “trapped” in the radiation-emitting body, whereby less radiation penetrates toward the outside.
U.S. Pat. No. 3,739,217 describes a radiation-emitting component comprising a radiation-emitting body having an uneven surface for improving the coupling-out of radiation. Radiation generated by the body that is subjected to total reflection at a radiation coupling-out surface opposite the uneven surface is deflected in the direction of the uneven surface, where the radiation is reflected in such a way that it can emerge from the body through the radiation coupling-out surface. The body is applied to a supporting, reflective baseplate on the side on which the uneven surface is situated.